## Algebraic & Geometric Topology

John A Baldwin

#### Abstract

For a word $w$ in the braid group $Bn$, we denote by $Tw$ the corresponding transverse braid in $(ℝ3,ξrot)$. We exhibit, for any two $g,h∈Bn$, a “comultiplication” map on link Floer homology $Φ̃:HFL˜(m(Thg))→HFL˜(m(Tg#Th))$ which sends $θ̃(Thg)$ to $θ̃(Tg#Th)$. We use this comultiplication map to generate infinitely many new examples of prime topological link types which are not transversely simple.

#### Article information

Source
Algebr. Geom. Topol., Volume 10, Number 3 (2010), 1417-1436.

Dates
Revised: 16 February 2010
Accepted: 21 February 2010
First available in Project Euclid: 19 December 2017

https://projecteuclid.org/euclid.agt/1513715141

Digital Object Identifier
doi:10.2140/agt.2010.10.1417

Mathematical Reviews number (MathSciNet)
MR2661532

Zentralblatt MATH identifier
1203.57004

#### Citation

Baldwin, John A. Comultiplication in link Floer homology and transversely nonsimple links. Algebr. Geom. Topol. 10 (2010), no. 3, 1417--1436. doi:10.2140/agt.2010.10.1417. https://projecteuclid.org/euclid.agt/1513715141

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